any other man wants to distinguish the true physician from the false,
how will he proceed? He will not talk to him about medicine; and that,
as we were saying, is the only thing which the physician understands.

True.

And, on the other hand, the physician knows nothing of science, for this
has been assumed to be the province of wisdom.

True.

And further, since medicine is science, we must infer that he does not
know anything of medicine.

Exactly.

Then the wise man may indeed know that the physician has some kind of
science or knowledge; but when he wants to discover the nature of this
he will ask, What is the subject-matter? For the several sciences are
distinguished not by the mere fact that they are sciences, but by the
nature of their subjects. Is not that true?

Quite true.

And medicine is distinguished from other sciences as having the
subject-matter of health and disease?

Yes.

And he who would enquire into the nature of medicine must pursue the
enquiry into health and disease, and not into what is extraneous?

True.

And he who judges rightly will judge of the physician as a physician in
what relates to these?

He will.

He will consider whether what he says is true, and whether what he does
is right, in relation to health and disease?

He will.

But can any one attain the knowledge of either unless he have a
knowledge of medicine?

He cannot.

No one at all, it would seem, except the physician can have this
knowledge; and therefore not the wise man; he would have to be a
physician as well as a wise man.

Very true.

Then, assuredly, wisdom or temperance, if only a science of science, and
of the absence of science or knowledge, will not be able to distinguish
the physician who knows from one who does not know but pretends or
thinks that he knows, or any other professor of anything at all; like
any other artist, he will only know his fellow in art or wisdom, and no
one else.

That is evident, he said.

But then what profit, Critias, I said, is there any longer in wisdom or
temperance which yet remains, if this is wisdom? If, indeed, as we were
supposing at first, the wise man had been able to distinguish what he
knew and did not know, and that he knew the one and did not know the
other, and to recognize a similar faculty of discernment in others,
there would certainly have been a great advantage in being wise; for
then we should never have made a mistake, but have passed thr